This application relates to magnetic resonance imaging.
Magnetic resonance imaging (MRI) uses magnetic resonances to acquire images in a wide range of imaging applications in medical, biological and other fields, including imaging various materials and body parts of a person or an animal. In essence, a typical MRI technique produces an image of a selected part of an object under examination by manipulating magnetic spins in the selected part and processing measured responses from the magnetic spins. An MRI system may include hardware to generate different magnetic fields for imaging, including a static magnetic field along a z-direction to polarize the magnetic spins, gradient fields along mutually orthogonal x, y, or z directions to spatially select a body part for imaging, and an RF magnetic field to manipulate the magnetic spins.
MRI detection is limited by the noise, which is usually characterized by the signal to noise ratio (SNR). In various MRI applications, it can be time consuming to acquire sufficient data to achieve a desired image quality (e.g., the image resolution and contrast). Considerable effort has been devoted to increasing the SNR in MRI and decreasing the scan time. However, trade-offs must be made between the SNR, the scan time, and also image quality.